Mobility enhancement in strained Si NMOSFETs with HfO/sub 2/ gate dielectrics

Abstract

Integration of strained Si and high-K gate dielectric is demonstrated for the first time. While providing a >1000/spl times/ gate leakage reduction, strained Si NMOSFETs with HfO/sub 2/ gate dielectric exhibit 60% higher mobility than the unstrained Si device with HfO/sub 2/ gate dielectrics, and 30% higher mobility than the conventional Si NMOSFETs with SiO/sub 2/ gate dielectric (universal MOSFET mobility).